Passive matrix display device and method of making the same

ABSTRACT

A passive matrix display device includes a first electrode panel including a first substrate, a plurality of anisotropic conductive lines extending in a first direction, and a plurality of first electrodes, each of the first electrodes including some of the plurality of anisotropic conductive lines, and others of the plurality of anisotropic conductive lines being arranged between and contacting both adjacent ones of the first electrodes; a second electrode panel including a second substrate, a plurality of anisotropic conductive lines extending in a second direction crossing the first direction, and a plurality of second electrodes, each of the second electrodes including some of the plurality of anisotropic conductive lines, and others of the plurality of anisotropic conductive lines being arranged between and contacting both adjacent ones of the second electrodes; and a display control medium between the first electrode panel and the second electrode panel.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application claims priority to and the benefit of U.S.Provisional Patent Application Ser. No. 62/031,778, entitled “METHOD TOCONSTRUCT CUSTOMIZABLE LOW-COST PASSIVE MATRIX DISPLAY DEVICE,” filed inthe United States Patent and Trademark Office on Jul. 31, 2014, theentire content of which is incorporated herein by reference.

BACKGROUND

1. Field

Embodiments of the present invention relate to a passive matrix displaydevice and a method of making the same.

2. Related Art

Recently, display devices have been increasingly used as, for example,an output and/or a user interface for electronic devices, such as mobilephones, televisions, electronic watches, and other various personalelectronic devices. Manufacturing such displays, including liquidcrystal displays (LCDs), organic light emitting diode (OLED) displays,and the like, is relatively expensive. For example, a process includingvarious specialized tooling and a carefully controlled environment maybe used to manufacture the display devices. Furthermore, the specializedtooling may only be suitable to manufacture a display device having acertain size, and other tooling may be necessary to manufacture adisplay device having a different size.

Accordingly, prototype display devices (or display devices manufacturedin relatively low quantities) are relatively expensive as specializedtooling may need to be manufactured or used to manufacture even a singleprototype display. Furthermore, the relatively high cost ofmanufacturing prototype display devices means that hobbyists and thelike cannot easily manufacture display devices for a specificapplication or project.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the invention, andtherefore, it may contain information that does not form prior art.

SUMMARY

Aspects of embodiments of the present invention include a passive matrixdisplay device and a method of making the passive matrix display device.

According to an embodiment of the present invention, a passive matrixdisplay device includes: a first electrode panel including a firstsubstrate, a plurality of anisotropic conductive lines on the firstsubstrate extending in a first direction, and a plurality of firstelectrodes, each of the first electrodes including some of the pluralityof anisotropic conductive lines, and others of the plurality ofanisotropic conductive lines being arranged between and contacting bothadjacent ones of the first electrodes; a second electrode panelincluding a second substrate, a plurality of anisotropic conductivelines on the second substrate extending in a second direction crossingthe first direction, and a plurality of second electrodes, each of thesecond electrodes including some of the plurality of anisotropicconductive lines, and others of the plurality of anisotropic conductivelines being arranged between and contacting both adjacent ones of thesecond electrodes; and a display control medium between the firstelectrode panel and the second electrode panel and configured to bevaried by an electric field generated between the first electrodes andthe second electrodes.

The anisotropic conductive lines may include carbon nanotubes.

The display control medium may include an electronic ink sheet.

The first electrode panel may further include a plurality of conductivetraces at a first end of the anisotropic conductive lines and definingthe first electrodes.

At least one of the plurality of conductive traces may have a differentlength than at least another one of the plurality of conductive traces.

The first electrode panel may further include another plurality ofconductive traces at a second end of the anisotropic conductive lines.

Ones of the plurality of conductive traces may be aligned withcorresponding ones of the other plurality of conductive traces.

The first electrode panel may further include a plurality of conductivelines and another plurality of conductive lines. Ones of the conductivelines may be connected to respective ones of the plurality of conductivetraces, and ones of the other plurality of conductive lines may beconnected to respective ones of the other plurality of conductivetraces.

Each of the other plurality of conductive lines may extend along oneside of the plurality of anisotropic conductive lines.

Some of the other plurality of conductive lines may extend along oneside of the plurality of anisotropic conductive lines, and others of theother plurality of conductive lines may extend along an opposite side ofthe plurality of anisotropic conductive lines.

According to an embodiment of the present invention, a method of makinga passive matrix display device includes: placing a plurality ofanisotropic conductive lines on a first substrate extending in a firstdirection, the plurality of anisotropic conductive lines forming acontinuous layer; placing a plurality of anisotropic conductive lines ona second substrate extending in a second direction crossing the firstdirection, the plurality of anisotropic conductive lines forming acontinuous layer; and arranging a display control medium between thefirst substrate and the second substrate.

The providing the plurality of anisotropic conductive lines may includemoving the first substrate with respect to a carbon nanotube ingot inthe first direction, while the first substrate is in contact with thecarbon nanotube ingot.

The method may further include forming a plurality of conductive tracesat a first end of the anisotropic conductive lines to define acorresponding plurality of first electrodes, adjacent ones of theplurality of conductive traces being spaced from each other.

Some of the plurality of anisotropic conductive lines may be arrangedbetween and may contact both adjacent ones of the plurality of firstelectrodes.

At least one of the plurality of conductive traces may have a lengthdifferent from at least another one of the plurality of conductivetraces.

The method may further include removing a portion of each of the firstsubstrate, the second substrate, and the display control medium.

After the removing the portion of each of the first substrate, thesecond substrate, and the display control medium, the passive matrixdisplay device may have a non-quadrangular shape.

According to an embodiment of the present invention, a passive matrixdisplay device includes a first electrode panel, a second electrodepanel, and a display control medium, and a method of making the passivematrix display device includes: forming a plurality of conductive traceson a first electrode panel, each of the plurality of conductive tracesextending across a plurality of anisotropic conductive lines on thefirst electrode panel; forming a plurality of conductive traces on asecond electrode panel, each of the plurality of conductive tracesextending across a plurality of anisotropic conductive lines on thesecond electrode panel; and arranging a display control medium betweenthe first electrode panel and the second electrode panel.

At least one of the plurality of conductive traces may have a lengththat is different from another one of the plurality of conductivetraces.

The method may further include removing a portion of the first electrodepanel, the second electrode panel, and the display control medium suchthat the passive matrix display device has a non-quadrangular shape.

Accordingly, a relatively low-cost, easily customizable passive matrixdisplay device and a method of making the same is provided.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the present invention, and many of theattendant features and aspects thereof, will become more readilyapparent as the invention becomes better understood by reference to thefollowing detailed description when considered in conjunction with theaccompanying drawings, in which:

FIG. 1 illustrates a display device according to an embodiment of thepresent invention;

FIG. 2 illustrates a first electrode panel of the display deviceaccording to an embodiment of the present invention;

FIG. 3 illustrates a second electrode panel of the display deviceaccording to an embodiment of the present invention;

FIG. 4 illustrates an assembled display panel according to an embodimentof the present invention;

FIG. 5 illustrates a second electrode panel of the display deviceaccording to an embodiment of the present invention;

FIG. 6 illustrates an assembled display panel according to an embodimentof the present invention;

FIG. 7 illustrates an assembled display panel and a controller accordingto an embodiment of the present invention; and

FIGS. 8 a-8 g illustrate a method of making a passive matrix displaydevice according to an embodiment of the present invention.

DETAILED DESCRIPTION

Hereinafter, example embodiments of the present invention will bedescribed in more detail with reference to the accompanying drawings.The present invention, however, may be embodied in various differentforms and should not be construed as being limited to only theembodiments illustrated herein. Rather, these embodiments are providedas examples so that this disclosure will be thorough and complete andwill fully convey some of the aspects and features of the presentinvention to those skilled in the art. Accordingly, processes, elements,and techniques that are not necessary for those having ordinary skill inthe art to have a complete understanding of the aspects and features ofthe present invention may not be described with respect to some of theembodiments of the present invention. Unless otherwise noted, likereference numerals denote like elements throughout the attached drawingsand the written description, and thus, descriptions thereof may not berepeated. In the drawings, the relative sizes of elements, layers, andregions may be exaggerated for clarity.

It will be understood that, although the terms “first,” “second,”“third,” etc. may be used herein to describe various elements,components, regions, layers, and/or sections, these elements,components, regions, layers, and/or sections should not be limited bythese terms. These terms are only used to distinguish one element,component, region, layer, or section from another element, component,region, layer, or section. Thus, a first element, component, region,layer, or section described below could be termed a second element,component, region, layer, or section without departing from the spiritand scope of the present invention.

Spatially relative terms, such as “beneath,” “below,” “lower,” “under,”“above,” “upper,” and the like, may be used herein for ease ofexplanation to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. It will beunderstood that the spatially relative terms are intended to encompassdifferent orientations of the device in use or in operation, in additionto the orientation depicted in the figures. For example, if the devicein the figures is turned over, elements described as “below” or“beneath” or “under” other elements or features would then be oriented“above” the other elements or features. Thus, the example terms “below”and “under” can encompass both an orientation of above and below. Thedevice may be otherwise oriented (e.g., rotated 90 degrees or at otherorientations) and the spatially relative descriptors used herein shouldbe interpreted accordingly. In addition, it will also be understood thatwhen an element or layer is referred to as being “between” two elementsor layers, it can be the only element or layer between the two elementsor layers or one or more intervening elements or layers may also bepresent.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the presentinvention. As used herein, the singular forms “a” and “an” are intendedto include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“includes,” “including,” “comprises,” and/or “comprising,” when used inthis specification, specify the presence of the stated features,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. As used herein, the term “and/or” includes any and allcombinations of one or more of the associated listed items. Expressions,such as “at least one of,” when preceding a list of elements, modify theentire list of elements and do not modify the individual elements of thelist. Further, the use of “may” when describing embodiments of thepresent invention refers to “one or more S embodiments of the presentinvention.” Also, the term “exemplary” is intended to refer to anexample or illustration.

It will be understood that when an element or layer is referred to asbeing “on,” “connected to,” “coupled to,” or “adjacent to” anotherelement or layer, it can be directly on, connected to, coupled to, oradjacent to the other element or layer, or one or more interveningelements or layers may be present. However, when an element or layer isreferred to as being “directly on,” “directly connected to,” “directlycoupled to,” or “immediately adjacent to” another element or layer,there are no intervening elements or layers present.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which the present invention belongs. Itwill be further understood that terms, such as those defined in commonlyused dictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art and/orthe present specification and should not be interpreted in an idealizedor overly formal sense, unless expressly so defined herein.

The controller and/or any other relevant devices or components accordingto embodiments of the present invention described herein may beimplemented utilizing any suitable hardware, firmware (e.g., anapplication-specific integrated circuit), software, or a suitablecombination of software, firmware, and hardware. For example, thevarious components of the controller may be formed on one integratedcircuit (IC) chip or on separate IC chips. Further, the variouscomponents of the controller may be implemented on a flexible printedcircuit film, a tape carrier package (TCP), a printed circuit board(PCB), or formed on a same substrate as the controller. Further, thevarious components of the controller may be a process or thread, runningon one or more processors, in one or more computing devices, executingcomputer program instructions and interacting with other systemcomponents for performing the various functionalities described herein.The computer program instructions are stored in a memory which may beimplemented in a computing device using a standard memory device, suchas, for example, a random access memory (RAM). The computer programinstructions may also be stored in other non-transitory computerreadable media such as, for example, a CD-ROM, flash drive, or the like.Also, a person of skill in the art should recognize that thefunctionality of various computing devices may be combined or integratedinto a single computing device, or the functionality of a particularcomputing device may be distributed across one or more other computingdevices without departing from the scope of the example embodiments ofthe present invention.

According to embodiments of the present invention, a relativelylow-cost, easily customizable passive matrix display device and a methodof making the same is provided. The passive matrix display device can beused as an output for an electronic device. For example, the passivematrix display device can be used as a prototype display for anelectronic device, a display for a small-quantity run of electronicdevices, or anywhere a passive matrix display device may be used. Inaddition, the passive matrix display device may be flexible by usingflexible substrates therein. Furthermore, a touch screen panel can beimplemented along with the passive matrix display device, thus providinga relatively low-cost, easily customizable user input device.

The passive matrix display device may be formed using carbon nanotubesas the electrodes. Carbon nanotubes have anisotropic conductivity (e.g.,are anisotropically conductive), meaning that the carbon nanotubesconduct electricity (electrons) along their length (e.g., along a longaxis of the nanotube) approximately 100 times better than they conductelectricity (electrons) in a direction perpendicular to their length(e.g., across a width or diameter of the nanotube). Accordingly, whenforming the electrodes using carbon nanotubes, adequate spacing betweenadjacent ones of the plurality of electrics and adjacent ones of theplurality of the carbon nanotubes does not need to be ensured (e.g.,adjacent carbon nanotubes may contact each other) due to theiranisotropic conductivity. For example, the carbon nanotubes may belayered on each other or may be formed in a continuous layer on asubstrate without transmitting or transferring an appreciable amount ofelectric current between each other (e.g., without demonstrating anyappreciable crosstalk therebetween).

Conventional electrodes, formed of compounds such as ITO (indium tinoxide) and the like, are generally equally or substantially equallyconductive along both their width and length directions. Accordingly,when using these compounds, such as ITO, to form the electrodes, thevarious electrodes should be spaced from each other (e.g., spaced apartfrom each other) so that they do not transmit electric current betweeneach other (e.g., to prevent crosstalk therebetween). Due to thisspacing, the forming of ITO electrodes is relatively expensive asspecialized tooling is generally used to ensure adequate spacing betweenthe various electrodes. Furthermore, the cost of ITO, for example, isincreasing as indium, a rare earth metal, becomes more expensive.

Accordingly, the passive matrix display device according to embodimentsof the present invention may be quickly and easily manufactured withoutthe use of specialized tooling.

Referring to FIG. 1, a display 1 includes a display panel 10, a bezel20, and an input connector 24. According to an embodiment of the presentinvention, the display panel 10 is a passive matrix display device andmay be an electronic ink display, a liquid crystal display, or the like.The input connector 24 may be any suitable connector, for example, a VGAinput, an HDMI input, a USB input, or the like. The bezel 20 may beprovided around a periphery of the display panel 10 to cover ancillarycomponents, such as a controller, power supply, and the like.

The display panel 10 includes a first electrode panel 100 (see FIG. 2),a second electrode panel 200 (see FIG. 3), and a suitable display medium(e.g., a suitable display control medium) therebetween. As will befurther described later, the display medium (or display control medium)may be an electronic ink sheet, a liquid crystal layer, or the like.

Referring to FIG. 2, the first electrode panel 100 (e.g., a frontelectrode panel) according to an embodiment of the present inventionincludes a substrate 110 (e.g., a first substrate) and a plurality ofconductive elements 111 (e.g., anisotropic conductive elements or lines)extending in a column direction, a plurality of conductive traces 112extending perpendicular to and across ends (e.g., across portionsadjacent ends) of the conductive elements 111, a plurality of conductivelines 113, and a plurality of connector pads 121 on the substrate 110.The substrate 110 may have a connector portion 120 on which theconnector pads 121 are formed. The connector portion 120 may protrudefrom an edge of the substrate 110, but the present invention is notlimited thereto. For example, the connector portion 120 may be an edgeportion of the substrate 110 that does not protrude therefrom.

The substrate 110 may be made of, for example, plastic, glass, or anyother suitable material. The substrate 110 may be transparent, opaque,or translucent. The substrate 110 may be flexible.

The conductive elements 111 may be transparent and/or may be formedsmall enough such that they are not visible (e.g., are virtuallyinvisible) to a viewer. For example, the conductive elements 111 may notsubstantially interfere with a displayed image. The conductive elements111 may be, for example, carbon nanotubes, silver and/or coppernanowires, a copper mesh patterned into strips, and/or the like. Anymaterial that demonstrates anisotropic conductivity may be a suitableelectrode. In one example, a material that exhibits less than 1%crosstalk may be a suitable electrode. When the conductive elements 111are carbon nanotubes, the conductive elements 111 may extend generallyin a column direction and may have some local variations in theirrespective extension direction. For example, as is illustrated in FIG. 8b, the carbon nanotubes may be wavy or slightly bent or curved alongtheir length. However, this waviness or bending will not substantiallyaffect performance of the display and may prevent or reduce generationof a moire pattern. Also, because carbon nanotubes are anisotropicallyconductive, various carbon nanotubes may contact each other withoutsubstantially affecting the performance of the display as there isrelatively little crosstalk therebetween (e.g., less than 1% crosstalk)even when the carbon nanotubes contact each other. For example, thecarbon nanotubes forming one electrode may contact other carbonnanotubes forming another electrode, or other carbon nanotubes notforming an electrode may contact adjacent carbon nanotubes that do formelectrodes without substantially affecting the performance of thedisplay device.

When the conductive elements 111 are silver and/or copper nanowires orcopper strips, each of the conductive elements 111 may be spaced fromadjacent conductive elements 111 to reduce or prevent crosstalktherebetween. However, if the nanowires used as the conductive elements111 are sufficiently anisotropically conductive, the various nanowiresor strips may contact each other without significantly affecting theperformance of the display device as described above with respect to thecarbon nanotubes.

The conductive traces 112 are each connected to a plurality of theconductive elements 111 to define electrodes (e.g., first electrodes) ofthe first electrode panel 100. For example, a first conductive trace 112is connected to (e.g., contacts or extends across) a first group of theconductive elements 111 to define an electrode, a second conductivetrace 112 is connected to a second group of the conductive elements 111to define another electrode, etc. As will be further described later, alength of each of the conductive traces 112 determines a width of eachpixel aligned with that respective column. The length of each of theconductive traces 112 may vary (e.g., the length of various ones of theconductive traces 112 may be different from each other). For example,the length of the conductive traces 112 near an edge of the substrate110 may be greater than a length of the conductive traces 112 near acenter of the substrate 110, but the present invention is not limitedthereto.

Adjacent ones of the conductive traces 112 may be spaced from each other(e.g., spaced apart from each other). However, one or more conductiveelements 111 may be between adjacent conductive traces 112 and betweenthe conductive elements 111 that form the various electrodes. Thus, thevarious electrodes may contact each other through ones of the conductiveelements 111 between the adjacent electrodes (e.g., conductive elements111 that do not form an electrode may be between and may contactadjacent electrodes). However, because the conductive elements 111 areanisotropically conductive as described above, electric transmission ortransmittance between adjacent electrodes is minimal or is preventedaltogether. Accordingly, the first electrode panel may be easilymanufactured without regard as to the presence of conductive elements111 arranged between and/or connecting adjacent electrodes.

The conductive lines 113 extend between and electrically connect ones ofthe conductive traces 112 to corresponding ones of the connector pads121. The conductive lines 113 permit a driving signal transmitted from acontroller to be sent to respective ones of the conductive traces 112 toenergize the corresponding electrodes (e.g., the correspondingconductive elements 111).

The conductive traces 112, the conductive lines 113, and the connectorpads 121 may each be formed of the same material or may be formed ofdifferent materials. For example, these components may be formed of aconductive ink including, for example, silver, copper, or any suitablematerial. The conductive traces 112 and the conductive lines 113 may beprinted using, for example, an inkjet printer, or drawn using a pendispenser. Thus, the conductive traces 112 and the conductive lines 113may be easily customized by, for example, varying a length thereof orconnection structure therebetween according to the specific display thatis desired without requiring specialized tooling. The connector pads 121may be pre-formed on the substrate 110 to correspond to a connectorextending from the controller or may be printed or drawn similar to theconductive traces 112 and the conductive lines 113 to be easilycustomized.

Referring to FIG. 3, the second electrode panel 200 (e.g., a rearelectrode panel) according to an embodiment of the present inventionincludes a substrate 210 and a plurality of conductive elements 211(e.g., anisotropic conductive elements or lines) extending in a rowdirection crossing the column direction, a plurality of conductivetraces 212, a plurality of conductive lines 213, and a plurality ofconnector pads 221 on the substrate 210. The connector pads 221 may beformed on a connector portion 220 of the substrate 210 which mayprotrude from an edge of the substrate 210; however, the presentinvention is not limited thereto, and the connector portion 220 may bean edge portion of the substrate 210 that does not protrude therefrom.

The conductive elements 211 may be the same or substantially the same asthe conductive elements 111 described above with respect to FIG. 1,except the conductive elements 211 extend in the row direction crossingthe column direction. However, the present invention is not limitedthereto, and the conductive elements 211 may extend in any direction,for example, 45° with respect to the extension direction of theconductive elements 111.

The conductive traces 212, the conductive lines 213, and the connectorpads 221 may substantially correspond to the conductive traces 112, theconductive lines 113, and the connector pads 121, respectively,described above with reference to FIG. 2. Thus, a detailed descriptionof these components may be omitted.

A body portion of the substrate 110 (e.g., a portion of the substrate110 other than the protruding connector portion 120) and a body portionof the substrate 210 (e.g., a portion of the substrate 210 other thanthe protruding connector portion 220) may have the same or substantiallythe same size. Furthermore, the connector portion 120 and the connectorportion 220 may protrude from different areas of the body of thesubstrate 110 and the body of the substrate 210, respectively, such thatwhen the substrates 110 and 210 are aligned with each other (e.g.,stacked on each other) the connector portions 120 and 220 do not overlapwith each other. Furthermore, portions of the substrates 110 and 210 onwhich the conductive elements 111 and 211 are respectively formed mayoverlap when the substrates 110 and 210 are aligned.

The substrate 210 may be transparent or opaque. However, at least one ofthe first or second substrate 110 or 210 is transparent to allow adisplayed image to be transmitted therethrough and be visible to aviewer.

Referring to FIG. 4, an assembled display panel 300 according to anembodiment of the present invention includes the first electrode panel100 and the second electrode panel 200 with a display medium 310 (e.g.,a display control medium) therebetween (see FIG. 8 e). In FIG. 4, theindividual components of the second electrode panel 200 are illustratedmerely for convenience of explanation and would not be visible (e.g.,would be virtually invisible) to a viewer viewing the assembled displaypanel 300. For example, the conductive elements 211 of the secondelectrode panel 200 would not substantially interfere with a displayedimage. Furthermore, the first electrode panel 100 and the secondelectrode panel 200 may be arranged such that respective sides of thefirst and second electrode panels 100 and 200 on which the conductiveelements 111 and 211 are respectively formed face the display medium310.

The display medium 310 may be an electronic ink sheet, a liquid crystallayer, or any other suitable medium. Furthermore, the conductiveelements 111 extending in the column direction and the conductiveelements 211 extending in the row direction form a matrix arrangement.For example, the groups of the conductive elements 111 formed by theconductive traces 112 (e.g., the first electrodes) cross the groups ofthe conductive elements 211 formed by the conductive traces 212 (e.g.,the second electrodes).

Hereinafter, a driving method of the assembled display panel 300according to an embodiment of the present invention will be described.As described above, the groups of the conductive elements 111 and 211(e.g., the first electrodes and the second electrodes, respectively) arearranged in a matrix. The controller sends electrical signals (e.g.,applies voltages) to various connector pads 121 and 221. The electricalsignals are transmitted through the corresponding conductive lines 113to the corresponding conductive traces 112 and through the correspondingconductive lines 213 to the corresponding conductive traces 212. Then,the electrical signals are conducted along the corresponding groups ofthe conductive elements 111 (e.g., along the corresponding firstelectrodes) and along the corresponding groups of the conductiveelements 211 (e.g., along the corresponding second electrodes). When onegroup of the conductive elements 111 is energized (e.g., receive thesignal from the controller) and one group of the conductive elements 211is energized at a different level or voltage, an electric field isgenerated where the groups of the conductive elements 111 and 211 crosseach other. The display medium 310 may be changed at where the electricfield is created.

For example, when the display medium 310 is an electronic ink sheet, theelectronic ink particles may be arranged within microcapsules to expresseither a dark or light color (e.g., express either black or white color)according to the direction of the applied electric field (e.g.,according to how the conductive elements 111 and the conductive elements211 are energized).

As another example, when the display medium 310 is the liquid crystallayer, the applied electric field acts on liquid crystals in the liquidcrystal layer to selectively allow light (e.g., light emitted from abacklight) to pass therethrough, thus displaying an image. In addition,when the display medium 310 is the liquid crystal layer, a polarizer maybe additionally included over the assembled display panel 300. However,the present invention is not limited to the above display mediums, andany suitable display medium may be included in the assembled displaypanel 300.

Furthermore, because the various conductive traces 112 and 212 may beformed to have varying lengths, the assembled display panel 300 may havea custom and/or varying dot pitch at different regions thereof. Forexample, the dot pitch of the assembled display panel 300 at a centerthereof may be less than the dot pitch at a periphery thereof. In oneexample, when a touch screen panel is included on the assembled displaypanel 300, a dot pitch at a bottom edge (e.g., a bottom periphery) ofthe assembled display panel 300 may be relatively large as visualindicators (e.g., buttons) may be displayed there that correspond toportions of the touch panel so a user may interact with the assembleddisplay panel 300. A relatively large dot pitch may be used in this areato simplify a driving method of the assembled display panel 300 byreducing the number of groups of conductive elements 111 and 211 in thedisplay without substantially affecting the quality of the display.

Referring to FIG. 5, the second electrode panel 200 according to anotherembodiment of the present invention includes another plurality ofconductive traces 212 and corresponding conductive lines 213. The otherplurality of conductive traces 212 are at an opposite end of theconductive elements 211 and are aligned with ones of the plurality ofconductive traces 212 at a first end (e.g., the end adjacent theconnector portion 220) of the conductive elements 211. Furthermore, someof the additional conductive lines 213 may extend along one side of theconductive elements 211 and others of the additional conductive lines213 may along an opposite side of the conductive elements 211 to beconnected to the connector pads 221. In another embodiment, theadditional conductive lines 213 may each extend along one side of theconductive elements 211 to be connected to the connector pads 221. Thearrangement of the additional conductive lines 213 may be determinedaccording to a desired final shape of the assembled display. Forexample, if a bottom right corner of the assembled display is desired tobe shaped, the additional conductive lines 213 may extend along an upperside of the conductive elements 211 to be connected to the connectorpads 221 so as to be not be cut when the assembled device is formed orshaped.

Similar to the second electrode panel 200 illustrated in FIG. 5, thefirst electrode panel 100 may include additional conductive traces 112and conductive lines 113. However, because their structure is the sameor substantially the same as that of the second electrode panel 200shown in FIG. 5, a detailed description thereof may be omitted.

Furthermore, the additional conductive lines 213 may be connected toseparate connector pads 221 or may be connected to corresponding ones ofthe conductive lines 213. For example, one of the conductive lines 213connected to one of the conductive traces 212 may be connected to orformed integrally with another one of the conductive lines 213 that isconnected to the conductive trace 212 that is aligned with the oneconductive trace 212, thus reducing the number of connector pads 221 andallowing the display to be more easily driven.

The additional conductive traces 212 may allow the electrical signals tobe more evenly applied to the electrodes, thus reducing or preventingdegradation of a display image along a length and/or width of thedisplay. Furthermore, the additional conductive traces allow an opening(e.g., a hole) or the like to be formed or cut in the assembled displaypanel 300 without affecting the display. For example, because a voltageis applied to both ends of the conductive elements 111 and 211,respectively, even if individual conductive elements 111 and 211 are cutor severed along their length, the voltage is still applied to each endof the conductive elements 111 or 211 via the additional conductivetraces 112 and 212, respectively.

Referring to FIG. 6, the assembled display panel 300 may be customized(e.g., made to have a certain desired shape) by a user. For example, theuser may form (e.g., shape or cut) the assembled display panel 300 usingscissors, a knife, a laser, or the like to cut through the firstelectrode panel 100, the display medium 310, and the second electrodepanel 200. In one example, when the desired dimensions of the assembleddisplay panel 300 are not known until after completion of the assembleddisplay panel 300, the assembled display may be easily cut or shaped tohave the desired dimensions without affect the quality of the display.In another example, the assembled display panel 300 may be shaped tohave a cut corner 320 (e.g., an inwardly rounded corner); however; thepresent invention is not limited thereto, and the assembled displaypanel 300 may be formed or shaped to have any suitable shape.

Referring to FIG. 7, the assembled display panel 300 may be connected toa controller 500 via a connector 400. The controller 500 may beconnected to the input connector 24 (see FIG. 1) to receive informationfrom an external device or input. The controller 500 may convert thereceived information into a suitable format to respectively control thevarious conductive elements 111 and 211 (e.g., apply signals to theconductive elements 111 and 211, respectively) to display an inputimage. The controller 500 may be set to refresh the assembled displaypanel 300 at a rate, for example, 60 Hz or 120 Hz or at any suitablerate.

The connector 400 may connect the controller 500 to the assembleddisplay panel 300 (e.g., to the first electrode panel 100 and the secondelectrode panel 200) via the connector portions 120 and 220. Forexample, the connector 400 may have pads that contact (e.g., connect to)the various connector pads 121 and 221. The connector 400 may be fixedto (e.g., soldered to) the connector portions 120 and 220 or may beremovably connected to the connector portions 120 and 220 by, forexample, a friction lock between the connector 400 and the connectorportions 120 and 220. However, the present invention is not limitedthereto, and any suitable connection structure may be used between thecontroller 500 and the assembled display panel 300.

Referring to FIGS. 8 a-8 g, a method of manufacturing a passive matrixdisplay device according to an embodiment of the present invention willbe described. Throughout the following description, a method ofmanufacturing one of the electrode panels is described for convenience.A description of a method of manufacturing the other of the electrodepanels may be omitted as the method is the same or substantially similarto the method of manufacturing the one of the electrode panels except asspecifically noted.

Referring to FIG. 8 a, the substrate 210 is moved over (e.g., draggedover) a carbon nanotube ingot 270. For example, the substrate 210,formed of, for example, plastic or glass, is placed on the carbonnanotube ingot 270, pressure is applied to the substrate 210 in adirection toward the ingot 270, and the substrate 210 and/or the ingot270 is then moved in the direction along which the resulting carbonnanotubes are desired to extend (e.g., the column direction or the rowdirection). As shown in FIG. 8 a, the carbon nanotubes extend in the rowdirection of the substrate 210, and the substrate 210 and/or the ingot270 are moved in the direction indicated by the arrow. After the carbonnanotubes are on the substrate 210, the process is similarly performedon another substrate, except the other substrate and/the ingot is movedto provide carbon nanotubes in a column direction (or any other suitabledirection) on the other substrate. The carbon nanotubes thus form theconductive elements 111 and 211 as described above.

The connector pads 221 may be formed on the substrate 210 prior toplacing of the conductive elements 211 thereon, or the connector pads221 may be formed on the substrate 210 after the conductive elements 211are placed thereon.

Because the carbon nanotubes are anisotropically conductive, they can bequickly and easily provided to the substrate without regard to spacingtherebetween or precise orientation. As shown in FIG. 8 b, the carbonnanotubes may not extend exactly along the column or row direction butmay have local variations (e.g., may be wavy, curved, or bent). However,these local variations do not negatively affect performance of thedisplay. As described above, the conductive elements 111 and 211 are notlimited to the carbon nanotubes but may be formed of silver and/orcopper nanowires or a copper mesh that is patterned into strips or linesusing methods known to those skilled in the art.

Referring to FIG. 8 c, a dispenser 140 is used to apply the conductivetraces 112 at one end of the conductive elements 111. The dispenser 140may be a conductive ink pen, an inkjet printer nozzle, and/or the like.Furthermore, the dispenser 140 may be selectively controlled to form theconductive traces 112 having certain lengths. For example, theconductive traces 112 may have different lengths from each other toproduce a desired dot pitch in the assembled display panel 300.

Referring to FIG. 8 d, the dispenser 140 may be used to form theconductive lines 113 which connect ones of the conductive traces 112 torespective ones of the connector pads 121. The same material that formsthe conductive traces 112 may form the conductive lines 113 or adifferent material may be used. Further, the same dispenser 140 that isused to form the conductive traces 112 may be used to form theconductive lines 113 or a different dispenser may be used. For example,an inkjet printer may be used to form the conductive traces 112 and aconductive pen may be used to form the conductive lines 113 or viceversa.

Referring to FIG. 8 e, once the first electrode panel 100 and the secondelectrode panel 200 are formed as described above, the display medium310 is arranged between the first electrode panel 100 and the secondelectrode panel 200. The first and second electrode panels 100 and 200are arranged such that the conductive elements 111 and 211 respectivelyface toward the display medium 310. The first electrode panel 100, thedisplay medium 310, and the second electrode panel 200 may then bejoined together to form the assembled display panel 300 (see FIG. 8 f).

Referring to FIG. 8 f, a sealant may be provided along an outerperiphery of the assembled display panel 300 to join these componentstogether and seal these components from the elements, such as moistureand oxygen. Alternatively, if further shaping or forming of theassembled display panel 300 is desired, the sealant may be applied afterthe further shaping or forming of the assembled display panel 300 iscompleted.

Referring to FIG. 8 g, if desired, the assembled display panel 300 maybe shaped or formed by using any suitable cutting device that canpenetrate the substrates and the display medium, such as scissors 330, aknife, a laser, and/or the like. Any suitable shape can be formed in theassembled display panel 300, such as an inwardly rounded corner 320. Inanother example, the overall dimensions of the display may be reducedwhile maintaining an aspect ratio, such as 4:3, 16:9, or 16:10. In yetanother embodiment, as described above, when the conductive traces 112and 212 are formed at opposite ends of the conductive elements 111 and211, respectively, shapes may be formed or cut in a center portion(e.g., a portion that does not extend to an edge) of the assembleddisplay panel 300, for example, an opening shaped as a hole, arectangular, or any other shape.

While the present invention has been described in connection withcertain example embodiments, it is to be understood that the inventionis not limited to the disclosed embodiments, but is intended to covervarious modifications and equivalent arrangements included within thespirit and scope of the appended claims and equivalents thereof.

What is claimed is:
 1. A passive matrix display device comprising: afirst electrode panel comprising a first substrate, a plurality ofanisotropic conductive lines on the first substrate extending in a firstdirection, and a plurality of first electrodes, each of the firstelectrodes comprising some of the plurality of anisotropic conductivelines, and others of the plurality of anisotropic conductive lines beingarranged between and contacting both adjacent ones of the firstelectrodes; a second electrode panel comprising a second substrate, aplurality of anisotropic conductive lines on the second substrateextending in a second direction crossing the first direction, and aplurality of second electrodes, each of the second electrodes comprisingsome of the plurality of anisotropic conductive lines, and others of theplurality of anisotropic conductive lines being arranged between andcontacting both adjacent ones of the second electrodes; and a displaycontrol medium between the first electrode panel and the secondelectrode panel configured to be varied by an electric field generatedbetween the first electrodes and the second electrodes.
 2. The passivematrix display device of claim 1, wherein the anisotropic conductivelines comprise carbon nanotubes.
 3. The passive matrix display device ofclaim 1, wherein the display control medium comprises an electronic inksheet.
 4. The passive matrix display device of claim 1, wherein thefirst electrode panel further comprises a plurality of conductive tracesat a first end of the anisotropic conductive lines and defining thefirst electrodes.
 5. The passive matrix display device of claim 4,wherein at least one of the plurality of conductive traces has adifferent length than at least another one of the plurality ofconductive traces.
 6. The passive matrix display device of claim 4,wherein the first electrode panel further comprises another plurality ofconductive traces at a second end of the anisotropic conductive lines.7. The passive matrix display device of claim 6, wherein ones of theplurality of conductive traces are aligned with corresponding ones ofthe other plurality of conductive traces.
 8. The passive matrix displaydevice of claim 6, wherein the first electrode panel further comprises aplurality of conductive lines and another plurality of conductive lines,wherein ones of the conductive lines are connected to respective ones ofthe plurality of conductive traces, and wherein ones of the otherplurality of conductive lines are connected to respective ones of theother plurality of conductive traces.
 9. The passive matrix displaydevice of claim 8, wherein each of the other plurality of conductivelines extends along one side of the plurality of anisotropic conductivelines.
 10. The passive matrix display device of claim 8, wherein some ofthe other plurality of conductive lines extend along one side of theplurality of anisotropic conductive lines, and others of the otherplurality of conductive lines extend along an opposite side of theplurality of anisotropic conductive lines.
 11. A method of making apassive matrix display device, the method comprising: placing aplurality of anisotropic conductive lines on a first substrate extendingin a first direction, the plurality of anisotropic conductive linesforming a continuous layer; placing a plurality of anisotropicconductive lines on a second substrate extending in a second directioncrossing the first direction, the plurality of anisotropic conductivelines forming a continuous layer; and arranging a display control mediumbetween the first substrate and the second substrate.
 12. The method ofclaim 11, wherein the providing the plurality of anisotropic conductivelines comprises moving the first substrate with respect to a carbonnanotube ingot in the first direction, while the first substrate is incontact with the carbon nanotube ingot.
 13. The method of claim 11,further comprising forming a plurality of conductive traces at a firstend of the anisotropic conductive lines to define a correspondingplurality of first electrodes, adjacent ones of the plurality ofconductive traces being spaced from each other.
 14. The method of claim13, wherein some of the plurality of anisotropic conductive lines arearranged between and contact both adjacent ones of the plurality offirst electrodes.
 15. The method of claim 13, wherein at least one ofthe plurality of conductive traces has a length different from at leastanother one of the plurality of conductive traces.
 16. The method ofclaim 11, further comprising removing a portion of each of the firstsubstrate, the second substrate, and the display control medium.
 17. Themethod of claim 16, wherein after the removing the portion of each ofthe first substrate, the second substrate, and the display controlmedium, the passive matrix display device has a non-quadrangular shape.18. A method of making a passive matrix display device comprising afirst electrode panel, a second electrode panel, and a display controlmedium, the method comprising: forming a plurality of conductive traceson a first electrode panel, each of the plurality of conductive tracesextending across a plurality of anisotropic conductive lines on thefirst electrode panel; forming a plurality of conductive traces on asecond electrode panel, each of the plurality of conductive tracesextending across a plurality of anisotropic conductive lines on thesecond electrode panel; and arranging a display control medium betweenthe first electrode panel and the second electrode panel.
 19. The methodof claim 18, wherein at least one of the plurality of conductive traceshas a length that is different from another one of the plurality ofconductive traces.
 20. The method of claim 18, further comprisingremoving a portion of the first electrode panel, the second electrodepanel, and the display control medium such that the passive matrixdisplay device has a non-quadrangular shape.